/ How long a rope for abseiling on the Skye Cuillin ridge?

Hi all
I'm hoping to do the ridge sometime soon and I don't want to be burdened down with any heavier gear than necessary. So as a competent climber, I'm just wondering what the shortest doubled rope is that I can get away with for the required abs?

In reply to mattrm: Just done Greater Cuillin Traverse and can confirm 35m rope is plenty long enough. Used a single 35m rope and was fine for TD Gap, King's Chimney, In Pinn and Naismiths (as 2 pitches) and all the abs.

In reply to Ron Kenyon: I did the same with 17m a couple of years ago. I'd experimented with 35m but found it a real hassle stopping the tangles.
Had planned to abandon the 17m length tied off to the Pinn chain but decided against littering & investigate the old way of descending short end. The flake has a perfect wee pyramid top for running a rope over but was far more entertaining trying to hold the 6mm on while tying italian hitch with one hand!
Yet to find the balls to downclimb the short side unroped!